Method and apparatus for correcting failures in automated speech recognition systems

ABSTRACT

Systems and methods are disclosed and described for correcting errors in ASR transcriptions. For an incorrect transcription, different words or phrases from the transcription, and/or related words or phrases, are submitted as hint words to the ASR system, and the voice query is submitted again, to determine new transcriptions. This process is repeated with different transcription terms, until a different and more proper transcription is generated. This increases the accuracy of ASR systems.

BACKGROUND

Embodiments of the disclosure relate generally to automated speechrecognition. More specifically, embodiments of the disclosure relate tofailure correction in automated speech recognition systems.

SUMMARY

Recent technological advances have allowed the somewhat widespread useof automated speech recognition (ASR) tools, by which computing devicesconvert speech to text without human intervention. ASR tools have provenuseful in numerous applications, including voice user interfaces thatrely on speech-to-text tools to convert spoken commands to text that canbe interpreted, and speech-to-text processing that allows people toperform word processing tasks without typing.

ASR currently suffers from significant limitations, however. UnassistedASR tools often suffer from limited accuracy. In particular, ASR systemsoften have difficulty when dealing with words that sound identical orsimilar yet have different meanings such as “meet” and “meat,”difficult-to-pronounce words that are often spoken incorrectly to theASR tool, mispronounced words, and noise in the speech input signal.These and other factors result in decreased accuracy of the ASR systemand user frustration.

Accordingly, to overcome the lack of accuracy in ASR systems, systemsand methods are described herein for a computer-based process thatcorrects incorrect ASR transcriptions, by successively submitting wordsor phrases from the transcription, along with related words and phrases,as hint words to the ASR system, until a more proper transcription isgenerated. This increases the accuracy of ASR systems.

In one embodiment, correction of ASR transcriptions may be implementedas part of an electronic content search system of a media playbackinterface. More specifically, users may submit queries such as voicequeries to an electronic content search system, requesting content theymay wish to view. The search system may search for and retrieve suchcontent for the user, assisted by an ASR system which translates theuser's spoken words into text that may serve as, for example, keywordsof a content search. The search system may then return content results,which may be played for the user through the media playback interface.

As one example, when an incorrect transcription is output by an ASRsystem, terms (e.g., various words or phrases) of the transcription,along with associated terms, are successively submitted as hint words tothe ASR system along with the original voice input. For instance, movieor actor names detected in the transcription, along with terms relatedto those movie or actor names, may be submitted as hint words.Submission of different terms continues until a resulting transcriptionoutput from the ASR system differs from the original, erroneoustranscription. This new transcription may be deemed more likely to becorrect, and is thus submitted to the electronic content search system,whereupon it is more likely that electronic content properly responsiveto the user's query will be returned.

To avoid excessive use of ASR systems, which may be costly and/orcomputationally expensive, embodiments of the disclosure may first checkwhether errors in content searches are due to ASR transcription errors,or are due to errors elsewhere. In some embodiments, it may first bedetermined that an improper search was conducted by the electroniccontent search system, such as by detection of the search system's errormessages. If an improper search has occurred, it may then also bedetermined whether the occurrence of the improper search resulted froman incorrect ASR transcription, and if so, the above describedtranscription correction processes may be implemented to successivelysubmit different transcription terms, and associated terms, as hintwords until the transcription changes.

Detection of an improper search may be conducted in any manner. In oneembodiment, occurrence of improper searches may be determined accordingto any one or more of a number of factors, including whether no contentwas selected by the search system as a result of the user's query,whether content selected by the search system has a relevance score lessthan some predetermined value or values (i.e., whether it is deemed notrelevant or not responsive to the query), whether the terms of thetranscription are not connected or are weakly connected in a knowledgegraph of content terms, or whether the terms of the transcription havepopularity scores below some predetermined value or values.

Detection of an incorrect transcription may also be conducted in anymanner. In one embodiment, occurrence of incorrect transcriptions may bedetermined according to any one or more of a number of factors,including whether a transcription score or metric of the transcriptionis less than some predetermined value or values, whether one or moreterms of the transcription have a homonym and are thus likely to be theincorrect homonym, whether one or more terms of the transcription aredifficult to pronounce (e.g., have a pronunciation difficulty metricgreater than some predetermined value or values), whether the audioinput was excessively noisy, whether one or more terms is mispronounced,or whether the transcription is a single-word transcription or atranscription containing multiple words.

If the search was not improper, i.e., if the ASR and search systems bothperformed correctly and valid and responsive results were returned, thesystem may transmit for display representations of the selected orreturned content, so that the user may view these representations. Forexample, thumbnail images of selected content may be displayed for theuser, allowing him or her to select from thumbnails for viewing.

If the search was improper but did not result from an incorrecttranscription, i.e., if the improper search was not the fault of the ASRsystem, an error message may be generated to prompt action by otherelements of the system, and/or representations of the selected contentmay be transmitted for display to the user. That is, results may bedisplayed for the user even if they are incorrect or not relevant, whilethe system is prompted to fix the error in some other manner. An errormessage may also be generated if no subset of transcription termsresults in any new or different transcription. Here too, representationsof the selected content may be transmitted for display to the user evenif they are incorrect or not relevant, while the system is prompted tofix the error in some other manner.

In some embodiments of the disclosure, it may be possible to generatemultiple different transcriptions. That is, the successive submission ofdifferent transcription terms as hint words may eventually result inmore than one transcription that differs from the original incorrecttranscription. In this case, the most common of these differingtranscriptions may be selected and submitted to the content searchsystem, for subsequent transmission of selected content or itsrepresentations to the user.

BRIEF DESCRIPTION OF THE FIGURES

The above and other objects and advantages of the disclosure will beapparent upon consideration of the following detailed description, takenin conjunction with the accompanying drawings, in which like referencecharacters refer to like parts throughout, and in which:

FIG. 1 illustrates operation of a system for correcting errors in ASRsystems, constructed in accordance with embodiments of the disclosure;

FIG. 2 is a block diagram illustration of a system for implementingcorrection of ASR errors in accordance with embodiments of thedisclosure;

FIG. 3 is a generalized embodiment of illustrative electronic computingdevices constructed for use according to embodiments of the disclosure;

FIG. 4 is a generalized embodiment of an illustrative ASR serverconstructed for use according to embodiments of the disclosure;

FIG. 5 is a generalized embodiment of an illustrative content searchserver constructed for use according to embodiments of the disclosure;and

FIGS. 6-8 are flowcharts illustrating processing steps for correctingerrors in ASR systems, in accordance with embodiments of the disclosure.

DETAILED DESCRIPTION

In one embodiment, the disclosure relates to systems and methods forcorrecting errors in ASR transcriptions. For an incorrect transcription,different words or phrases from the transcription, and/or related wordsor phrases, are submitted as hint words to the ASR system, and the voicequery is submitted again, to determine new transcriptions. This processis repeated with different transcription terms, until a different andmore proper transcription is generated. This increases the accuracy ofASR systems.

Methods and systems of embodiments of the disclosure may be applied to,or utilized in, electronic content search systems, to improve theaccuracy of results generated by voice-based searches for electroniccontent. Embodiments of the disclosure thus may also include initiallydetermining whether errors or inaccuracies in such content searchesresult from incorrect ASR transcriptions.

FIG. 1 illustrates operation of a system for correcting errors in ASRsystems, constructed in accordance with embodiments of the disclosure.Here, a voice-based content interface system 100 includes an ASR system110 and a content search system 120. The ASR system 110 receives uservoice queries as input, and outputs corresponding transcriptions asnatural language text terms. The content search system 120 receives thistext as input and conducts searches for, in this case, electroniccontent, with output being either selected electronic content fortransmission to the user, or an error message.

In operation, system 100 may conduct an improper or non-responsivesearch, based on an improper transcription of the user's voice query.For example, a user may request the movie “Days of Thunder with TomCruise and Nicole Kidman.” The ASR module 110 may inadvertentlymis-transcribe this request as “Days of Wonder with Tom Cruise andNicole Kidman.” In this situation, content search system 120 would notbe able to find any such movie, and would accordingly return an errormessage such as “Sorry, I could not find that.”

In response, system 100 repeatedly attempts new translations of theaudio request, with each attempt using hint words derived from differentterms of the improper transcription. For example, the system 100 mayfirst attempt another transcription using the hint words “Days ofWonder” and/or any related hint words. In this case, as “Days of Wonder”may also refer to a music album by the group Magnum, related hint wordsinput to ASR 110 may include terms such as “music album,” “magnum,” andthe like. As these hint words are not related to the movie Days ofThunder, the resulting transcription is the same as the originalincorrect transcription.

System 100 may next attempt another transcription using hint wordsrelated to a different transcription term, such as “Tom Cruise.”Corresponding hint words may thus include terms such as his previousmovie “Mission: Impossible,” “action,” and the like. As the hint wordsin this case direct ASR module 110 toward Tom Cruise movies, theresulting transcription may be changed to “Days of Thunder with TomCruise and Nicole Kidman.”

As this new transcription differs from the original incorrecttranscription, the new transcription is input to content search system120. As the new transcription properly references existing content, thecontent search system 120 locates and returns the movie “Days ofThunder,” informing the user accordingly. In this manner, successivelyattempting new transcriptions with different hint words based ondifferent original transcription terms each attempt, may result ineventually determining the correct transcription, thus improving theaccuracy of content searches.

FIG. 2 is a block diagram illustration of a system for implementingcorrection of ASR errors, in accordance with embodiments of thedisclosure. A computing device 200 may be in communication with an ASRserver 220 through, for example, a communications network 210. ASRserver 220 is also in electronic communication with content searchserver 230 also through, for example, the communications network 210.Computing device 200 may be any computing device running a userinterface, such as a voice assistant, voice interface allowing forvoice-based communication with a user, or an electronic content displaysystem for a user. Examples of such computing devices are a smart homeassistant similar to a Google Home® device or an Amazon® Alexa® or Echo®device, a smartphone or laptop computer with a voice interfaceapplication for receiving and broadcasting information in voice format,a set-top box or television running a media guide program or othercontent display program for a user, or a server executing a contentdisplay application for generating content for display or broadcast to auser. ASR server 220 may be any server running an ASR application,including modules for implementing processes of embodiments of thedisclosure. Content search server 230 may be any server programmed tosearch for electronic content responsive to queries processed by the ASRserver 220. For example, content search server 230 may be a serverprogrammed to search content database 240 for content, and to returnselected content or representations thereof to one or more of ASR server220 or computing device 200.

The computing device 200 may be any device capable of acting as a voiceinterface system such as by running one or more application programsimplementing voice-based communication with a user, and engaging inelectronic communication with server 220. For example, computing device200 may be a voice assistant, smart home assistant, digital TV running acontent display interface, laptop computer, smartphone, tablet computer,or the like.

FIG. 3 shows a generalized embodiment of an illustrative user equipmentdevice 300 that may serve as a computing device 200. User equipmentdevice 300 may receive content and data via input/output (hereinafter“I/O”) path 302. I/O path 302 may provide content (e.g., broadcastprogramming, on-demand programming, Internet content, content availableover a local area network (LAN) or wide area network (WAN), and/or othercontent) and data to control circuitry 304, which includes processingcircuitry 306 and storage 308. Control circuitry 304 may be used to sendand receive commands, requests, and other suitable data using I/O path302. I/O path 302 may connect control circuitry 304 (and specificallyprocessing circuitry 306) to one or more communications paths (describedbelow). I/O functions may be provided by one or more of thesecommunications paths but are shown as a single path in FIG. 3 to avoidovercomplicating the drawing.

Control circuitry 304 may be based on any suitable processing circuitrysuch as processing circuitry 306. As referred to herein, processingcircuitry should be understood to mean circuitry based on one or moremicroprocessors, microcontrollers, digital signal processors,programmable logic devices, field-programmable gate arrays (FPGAs),application-specific integrated circuits (ASICs), etc., and may includea multi-core processor (e.g., dual-core, quad-core, hexa-core, or anysuitable number of cores). In some embodiments, processing circuitry maybe distributed across multiple separate processors or processing units,for example, multiple of the same type of processing units (e.g., twoIntel Core i7 processors) or multiple different processors (e.g., anIntel Core i5 processor and an Intel Core i7 processor). In someembodiments, control circuitry 304 executes instructions for receivingstreamed content and executing its display, such as executingapplication programs that provide interfaces for content providers tostream and display content on display 312.

Control circuitry 304 may thus include communications circuitry suitablefor communicating with ASR server 220, content search server 230, or anyother networks or servers. Communications circuitry may include a cablemodem, an integrated services digital network (ISDN) modem, a digitalsubscriber line (DSL) modem, a telephone modem, an Ethernet card, or awireless modem for communication with other equipment, or any othersuitable communications circuitry. Such communications may involve theInternet or any other suitable communications networks or paths. Inaddition, communications circuitry may include circuitry that enablespeer-to-peer communication of user equipment devices, or communicationof user equipment devices in locations remote from each other.

Memory may be an electronic storage device provided as storage 308,which is part of control circuitry 304. As referred to herein, thephrase “electronic storage device” or “storage device” should beunderstood to mean any device for storing electronic data, computersoftware, or firmware, such as random-access memory, read-only memory,hard drives, optical drives, digital video disc (DVD) recorders, compactdisc (CD) recorders, BLU-RAY disc (BD) recorders, BLU-RAY 3D discrecorders, digital video recorders (DVRs, sometimes called personalvideo recorders, or PVRs), solid state devices, quantum storage devices,gaming consoles, gaming media, or any other suitable fixed or removablestorage devices, and/or any combination of the same. Storage 308 may beused to store various types of content described herein as well as mediaguidance data described above. Nonvolatile memory may also be used(e.g., to launch a boot-up routine and other instructions). Cloud-basedstorage may be used to supplement storage 308 or instead of storage 308.

Storage 308 may also store instructions or code for an operating systemand any number of application programs to be executed by the operatingsystem. In operation, processing circuitry 306 retrieves and executesthe instructions stored in storage 308, to run both the operating systemand any application programs started by the user. The applicationprograms can include one or more voice interface applications forimplementing voice communication with a user, and/or content displayapplications that implement an interface allowing users to select anddisplay content on display 312 or another display.

Control circuitry 304 may include video generating circuitry and tuningcircuitry, such as one or more analog tuners, one or more MPEG-2decoders or other digital decoding circuitry, high-definition tuners, orany other suitable tuning or video circuits or combinations of suchcircuits. Encoding circuitry (e.g., for converting over-the-air, analog,or digital signals to MPEG signals for storage) may also be included.Control circuitry 304 may also include scaler circuitry for upconvertingand downconverting content into the preferred output format of the userequipment 300. Circuitry 304 may also include digital-to-analogconverter circuitry and analog-to-digital converter circuitry forconverting between digital and analog signals. The tuning and encodingcircuitry may be used by the user equipment device to receive and todisplay, to play, or to record content. The tuning and encodingcircuitry may also be used to receive guidance data. The circuitrydescribed herein, including for example, the tuning, video generating,encoding, decoding, encrypting, decrypting, scaler, and analog/digitalcircuitry, may be implemented using software running on one or moregeneral-purpose or specialized processors. Multiple tuners may beprovided to handle simultaneous tuning functions (e.g., watch and recordfunctions, picture-in-picture (PIP) functions, multiple-tuner recording,etc.). If storage 308 is provided as a separate device from userequipment 300, the tuning and encoding circuitry (including multipletuners) may be associated with storage 308.

A user may send instructions to control circuitry 304 using user inputinterface 310. User input interface 310 may be any suitable userinterface, such as a remote control, mouse, trackball, keypad, keyboard,touch-screen, touchpad, stylus input, joystick, voice recognitioninterface, or other user input interfaces. Display 312 may be providedas a stand-alone device or integrated with other elements of userequipment device 300. For example, display 312 may be a touchscreen ortouch-sensitive display. In such circumstances, user input interface 310may be integrated with or combined with display 312. Display 312 may beone or more of a monitor, a television, a liquid crystal display (LCD)for a mobile device, amorphous silicon display, low temperature polysilicon display, electronic ink display, electrophoretic display, activematrix display, electro-wetting display, electrofluidic display, cathoderay tube display, light-emitting diode display, electroluminescentdisplay, plasma display panel, high-performance addressing display,thin-film transistor display, organic light-emitting diode display,surface-conduction electron-emitter display (SED), laser television,carbon nanotubes, quantum dot display, interferometric modulatordisplay, or any other suitable equipment for displaying visual images.In some embodiments, display 312 may be HDTV-capable. In someembodiments, display 312 may be a 3D display, and the interactive mediaguidance application and any suitable content may be displayed in 3D. Avideo card or graphics card may generate the output to the display 312.The video card may offer various functions such as accelerated renderingof 3D scenes and 2D graphics, MPEG-2/MPEG-4 decoding, TV output, or theability to connect multiple monitors. The video card may be anyprocessing circuitry described above in relation to control circuitry304. The video card may be integrated with the control circuitry 304.Speakers 314 may be provided as integrated with other elements of userequipment device 300 or may be stand-alone units. The audio component ofvideos and other content displayed on display 312 may be played throughspeakers 314. In some embodiments, the audio may be distributed to areceiver (not shown), which processes and outputs the audio via speakers314.

FIG. 4 is a generalized embodiment of an illustrative ASR server 220constructed for use according to embodiments of the disclosure. Here,device 400 may serve as an ASR server. Device 400 may receive contentand data via I/O paths 402 and 404. I/O path 402 may provide content anddata to the various devices 200, 230, while I/O path 404 may providedata to, and receive content from, one or more content search servers230. Like the user equipment device 300, the device 400 has controlcircuitry 406, which includes processing circuitry 408 and storage 410.The control circuitry 406, processing circuitry 408, and storage 410 maybe constructed, and may operate, in a similar manner to the respectivecomponents of user equipment device 300.

Storage 410 is a memory that stores a number of programs for executionby processing circuitry 408. In particular, storage 410 may store anumber of device interfaces 412, an ASR module 414, hint words module416 for determining hint words and submitting them to ASR module 414,and error correction module 418. The device interfaces 412 are interfaceprograms for handling the exchange of commands and data with the variousdevices 200. ASR module 414 is one or more programs for carrying out theASR functions described herein, e.g., transcribing voice input receivedfrom devices 200. As above, ASR module 414 determines transcriptionsaided by hint words submitted by hint words module 416, and transmitsthe transcription to content search server 230. Hint words module 416includes code for executing all of the above described functions forselecting hint words, including retrieving terms from transcriptionsoutput by ASR module 414, selecting hint words therefrom, and sendingthe selected hint words to ASR module 414 to aid ASR module 414 intranscribing voice input. Error correction module 418 is a module forperforming the above-described error correction processes, initiatingsuccessive generation of hint words by module 416 for transcription ofvoice input by ASR module 414 until the output transcription differsfrom the original erroneous transcription.

The device 400 may be any electronic device capable of electroniccommunication with other devices and performance of ASR error correctionprocesses described herein. For example, the device 400 may be a server,or a networked in-home smart device connected to a home modem andthereby to various devices 200. The device 400 may alternatively be alaptop computer or desktop computer configured as above.

FIG. 5 is a generalized embodiment of an illustrative content searchserver 230 constructed for use according to embodiments of thedisclosure. Here, device 500 may serve as a content search server.Device 500 may receive content and data via I/O paths 502 and 504. I/Opath 502 may provide content and data to the various devices 200 and/orserver 220, while I/O path 504 may provide data to, and receive contentfrom, content database 240. Like the device 400, the device 500 hascontrol circuitry 506, which includes processing circuitry 508 andstorage 510. The control circuitry 506, processing circuitry 508, andstorage 510 may be constructed, and may operate, in a similar manner tothe respective components of device 400.

Storage 510 is a memory that stores a number of programs for executionby processing circuitry 508. In particular, storage 510 may store anumber of device interfaces 512, an ASR interface 514, content searchmodule 516 for searching electronic content entries stored in contentdatabase 240 according to transcribed queries from ASR server 220, anderror determination module 518 for determining and transmitting errorsin the search processes executed by content search module 516. Thedevice interfaces 512 are interface programs for handling the exchangeof commands and data with the various devices 200. ASR interface 514 isan interface program for handling the exchange of transcriptions, errormessages, instructions, and resulting search results with ASR server220. Content search module 516 includes code for executing all of theabove-described functions for carrying out searches for electroniccontent, including receiving transcribed queries from ASR module 414 ofASR server 220, conducting searches of content database 240 according tothe received transcriptions, and returning results and/or other data toone or more of ASR server 220 or device(s) 200. Error determinationmodule 518 is configured to determine whether errors occur in the searchprocesses of content search module 516, and to transmit any such errormessages to appropriate devices such as ASR server 220 or device(s) 200.

Any of the various modules and functions of servers 220 and 230 mayreside on any one or more devices. For example, ASR functionality andcontent search functionality may be combined on the same server, or evenwithin computing device 200.

FIG. 6 is a flowchart illustrating processing steps for correctingerrors in ASR systems, in accordance with embodiments of the disclosure.In particular, FIG. 6 describes the operation of servers 220 inconducting content searches responsive to voice queries. Here, errordetermination module 518 first determines the occurrence of an impropersearch conducted by the ASR system in response to a voice querysubmitted by a user of device 200 (Step 600). Error determination module518 may determine the occurrence of an improper search in any manner. Insome embodiments of the disclosure, errors may be determined accordingto a heuristic or factor-based approach using any one or more factors.One such factor may be whether no content was selected by the contentsearch module 516 in searching the content database 240 responsive tothe search text received from ASR module 414. A search that returns noresults may be deemed to be an unlikely, and thus improper, search.

Another factor may be whether the electronic content selected by thesearch module 516 has relevance scores less than some predeterminedvalue. Here, the presence of a number of irrelevant, or low-relevance,results may indicate a search unlikely to have been intended by theuser, and may thus be considered improper. Relevance scores are known,and may be determined in any manner. Additionally, any one or morerelevance scores may be employed, and compared to any one or morepredetermined values that are determined in any manner.

A further factor may be whether the terms of the transcription receivedfrom ASR module 414 are either not connected or weakly connected in aknowledge graph of terms of electronic content. That is, a knowledgegraph, e.g., a known graph data structure, constructed of terms used inor related to electronic content of interest, may be stored oraccessible by error determination module 518. The error determinationmodule 518 may determine the distances in this graph between variousterms of the transcription it receives and, if these terms areexcessively far apart or not connected (e.g., one or more transcriptionterms does not appear in the knowledge graph), this may weigh towardsdetermination of an error. Determination of weak connections may beperformed in any manner, such as by comparison to a predetermineddistance in the knowledge graph (which may be any distance), thepresence of a predetermined number of terms that are greater than somepredetermined distance from one another, or the like. Such predetermineddistances may be any distances, of any magnitude.

Another factor may be whether the terms of the transcription receivedfrom ASR module 414 have popularity scores below some predeterminedvalue. That is, error determination module 518 or another suitablemodule may determine popularity scores for terms of the receivedtranscription, or scores indicating how common or popular the terms are.Low popularity scores may indicate terms not often used and thusunlikely to intentionally appear in a query, thus indicating a likelymistake in the transcription or voice query. Popularity scores of termsare known, and may be determined in any manner. Further, popularityscores may be compared to any suitable predetermined value or valuesthat may indicate uncommon or unpopular terms.

Error determination module 518 may employ these or any other factors inany manner, to determine the occurrence of an improper search. Forexample, any one factor may be considered dispositive as desired, or anerror may be determined when greater than any predetermined number ofthe above or other factors are present. Alternatively, factors may eachbe assigned scores in any manner, and errors may be determined when thetotal of such scores for every factor exceeds some predetermined valueor values.

If the error determination module 518 determines that the search wasproper, search results may simply be delivered to the user. However, ifthe error determination module 518 determines that an improper searchhas been conducted, module 518 then determines whether the impropersearch resulted from an incorrect transcription, or from some othercause (Step 610). Error determination module 518 may determine anincorrect transcription in any manner. In some embodiments of thedisclosure, the presence of an incorrect transcription may be determinedaccording to a heuristic or factor-based approach using any one or morefactors. One such factor may be whether a transcription score of thetranscription corresponding to the improper search is less than somepredetermined value. Transcription scores are known, and may include anyscores characterizing the accuracy of a transcription. Here, lowtranscription scores may indicate a transcription that is unlikely to becorrect, or likely to contain one or more erroneous terms. Any one ormore transcription scores may be employed, and compared to any one ormore predetermined values that are determined in any manner.

Another factor may be whether one or more terms of the transcription ofan improper search have one or more homonyms, and thus were actuallyintended to be a different term, i.e., one of the homonyms. Words orterms with homonyms are thus more likely to be incorrect. To determinethe presence of homonyms, error determination module 518 may store alist of common homonyms, and compare transcription terms to entries ofthis list. Alternatively, homonym detection may be performed in anyother suitable manner.

A further factor may be whether one or more terms of the transcriptionof an improper search are difficult to pronounce, e.g., have apronunciation difficulty metric greater than some predetermined value.Pronunciation difficulty may be measured in any manner, such as bycomparing transcription terms to a stored list of difficult-to-pronounceterms, evaluating a pronunciation difficulty metric, or the like. Suchmetrics may be any one or more values or criteria suitable for measuringthe ease of pronunciation of a term, and may include comparison of thetranscription terms to stored difficult-to-pronounce syllables or lettercombinations, where the pronunciation difficult metric may be determinedaccording to the number of such syllables/letter combinations in thetranscription.

An additional factor may be the noise level of the recorded audio query,where high noise levels may indicate a greater likelihood of an impropertranscription. Determination of noise levels, and associated noise levelmetrics, are known, and embodiments of the disclosure contemplate bothnoise level determination and determination of excessive noise level inany manner.

A further factor may be whether any term of the transcription is amispronounced term, as mispronounced terms may indicate an impropertranscription. Mispronounced terms may be determined in any manner, suchas by comparison of the transcription to stored phoneme sequences knownto be mispronunciations, use of known machine learning methods foridentifying mispronounced terms, and the like.

Another factor may be whether there is more than one term in thetranscription, as successive submission of multiple transcription termsis not possible if only one term exists. Accordingly, a single-termtranscription may be deemed, in some embodiments of the disclosure, as acorrect transcription.

Error determination module 518 may employ these or any other factors inany manner, to determine that an improper search resulted from anincorrect transcription. For example, any one factor may be considereddispositive as desired (e.g., a single-term transcription), or an errormay be determined when greater than any predetermined number of theabove or other factors are present. Alternatively, factors may beassigned scores in any manner, and errors may be determined when thetotal of such scores for every factor exceeds some predetermined valueor values.

If error determination module 518 has determined that an improper searchoccurred, and that this improper search resulted from an incorrecttranscription, module 518 may then signal the ASR server 220 to performthe above-described ASR error correction methods, successivelysubmitting terms of the transcription, and/or any associated terms, ashint words to the ASR module 414 until the resulting transcriptiondiffers from the original, incorrect transcription (Step 620). Morespecifically, such a signal from module 518 may prompt ASR server 220 todirect hint words module 416 to select a set of terms related tosuccessive different terms of the incorrect transcription, and to submitthese sets of terms to the ASR module 414. The ASR module 414 thenre-transcribes the audio query from device 200 with each set of hintword terms, until one or more different transcriptions are produced(Step 620). Hint words module 416 may select related terms in anymanner, such as by maintaining a graph of content-related terms in knownmanner and selecting terms within a predetermined graph distance of eachsuccessive different transcription term.

Once one or more new transcriptions are generated, one such newtranscription is selected (if more than one exists) and submitted tocontent search server 230 so that it may search for and select contentcorresponding to the new transcription (Step 630). As above, searchserver 230 may search content database 240 or other content repositoriesfor content matching the transcription or query it receives from ASRserver 220, in known manner. Representations of selected content, suchas thumbnails, previews, or the like, may then be transmitted to thedevice 200, perhaps via ASR server 220 if desired, for viewing and/orselection by the user.

Embodiments of the disclosure contemplate the successive submission ofdiffering transcription terms, and associated terms, as hint words to anASR system at any time. For example, the ASR error correction processesof embodiments of the disclosure may be performed for every searchconducted by search server 230, as a verification or check.Alternatively, the ASR error correction processes of embodiments of thedisclosure may be performed for every improper search, regardless ofwhether an incorrect transcription is deemed to be at fault. However, toconserve resources (e.g., computational overhead, power, any monetarycosts associated with execution of ASR module 414, or the like) consumedby ASR error correction, some embodiments of the disclosure contemplateperformance of the ASR error correction methods described herein onlywhen an improper search has occurred, and this improper search is deemedto result from an incorrect transcription.

FIG. 7 is a flowchart illustrating conditional execution of ASR errorcorrection, in accordance with some such embodiments. Initially, errordetermination module 518 may determine whether content search module 516conducted an improper search (Step 700). Determination of an impropersearch may be conducted as described above in connection with Step 600of FIG. 6, weighing one or more factors to determine whether a searchshould be considered improper or erroneous.

If the error determination module 518 determines that the search was notimproper, e.g., if the search resulted in a sufficient amount ofrelevant content returned, the search server 230 may transmitrepresentations of the selected content to device 200, perhaps via ASRserver 220, for display by device 200 for the user (Step 710). In manycontent interfaces, users may then select content representations, suchas thumbnail images or icons, to receive a stream of the content forviewing. Conversely, if error determination module 518 determines thatthe search was an improper or erroneous search, e.g., if the searchresulted in no results, or the results were of poor relevance orcontained excessive low-popularity content, the error determinationmodule may then determine whether this was the fault of an incorrecttranscription (Step 720). Determination of an incorrect transcriptionmay be conducted as described above in connection with Step 610 of FIG.6, weighing one or more factors to determine whether an incorrecttranscription exists.

If the error determination module 518 determines that the transcriptionwas accurate or correct, e.g., when the transcription has a highaccuracy score, no difficult or mispronounced terms, and littleassociated noise, module 518 may generate an error message indicatingthe occurrence of an improper search (but one for which transcriptionwas not the cause) and transmit the returned results for the useranyway. That is, the search server 230 may transmit representations ofthe selected content to device 200, perhaps via ASR server 220, fordisplay by device 200 for the user (Step 740), even if the search isdeemed improper, as the user is likely to be more frustrated by noresults or an error message than at least some results, even if they maynot be to the user's liking.

Alternatively, if the error determination module 518 determines that thetranscription was inaccurate or incorrect, e.g., the transcription has alow accuracy score, several difficult-to-pronounce terms and manypotential homonyms, module 518 may instruct ASR server 220 to conductASR correction methods of embodiments of the disclosure, e.g., as inStep 620 above, performing successive submission of transcription termsand/or related terms as hint words to the ASR module 414 (Step 730)until the resulting transcription changes. In this manner, ASR errorcorrection processes may be performed only if an improper search hasoccurred and if this improper search is the result of an incorrect ASRtranscription, thus preventing wasted resources in executing ASRprocesses unnecessarily.

As above, ASR correction processes of embodiments of the disclosure mayresult in more than one transcription that differs from the originalerroneous transcription. That is, successively re-running the ASR module414 using different sets of hint words for different transcription termsmay result in multiple different transcriptions. In this situation,embodiments of the disclosure contemplate selection of any of these new,differing transcriptions as the correct transcription for executing anew content search. Transcription selection may be performed in anymanner.

FIG. 8 is a flowchart illustrating one such approach. Here, as above,when an improper content search is detected and is determined to resultfrom an incorrect ASR transcription, ASR server 220 may successivelysubmit different subsets of transcription terms, and/or any relatedterms, as hint words to ASR module 414 until multiple resultingtranscriptions differ from the original, incorrect transcription (Step800). ASR server 220 may then select the most common of the multipleresulting transcriptions (Step 810). If only one transcription differsfrom the original incorrect transcription, that one transcription isselected. The selected transcription is then submitted to the contentsearch server 230 for selection of content (Step 820). Any resultingcontent selections, or any representations thereof, may then betransmitted for display to the user (Step 830). Selection of the mostcommon of the new transcriptions may increase the likelihood ofselecting the correct transcription, thus improving search results.

The foregoing description, for purposes of explanation, used specificnomenclature to provide a thorough understanding of the disclosure.However, it will be apparent to one skilled in the art that the specificdetails are not required to practice the methods and systems of thedisclosure. Thus, the foregoing descriptions of specific embodiments ofthe present invention are presented for purposes of illustration anddescription. They are not intended to be exhaustive or to limit theinvention to the precise forms disclosed. Many modifications andvariations are possible in view of the above teachings. For example,improper searches and incorrect transcriptions can be detected ordetermined in any manner, and terms related to transcription terms mayalso be determined in any manner. The embodiments were chosen anddescribed in order to best explain the principles of the invention andits practical applications, to thereby enable others skilled in the artto best utilize the methods and systems of the disclosure and variousembodiments with various modifications as are suited to the particularuse contemplated. Additionally, different features of the variousembodiments, disclosed or otherwise, can be mixed and matched orotherwise combined so as to create further embodiments contemplated bythe disclosure.

1. A method of correcting errors in searches for electronic contentresulting from incorrect transcriptions by an automated speechrecognition system, the method comprising: for an incorrecttranscription output by one or more automated speech recognitionsystems, successively submitting, using control circuitry, termsassociated with different subsets of terms of the transcription as hintwords to the one or more automated speech recognition systems, until aresulting transcription output by the one or more automated speechrecognition systems differs from the incorrect transcription; andsubmitting the resulting transcription to an electronic content searchsystem for selecting electronic content corresponding to the resultingtranscription.
 2. The method of claim 1, further comprising: determiningan occurrence of an improper search conducted by the electronic contentsearch system; and determining whether the occurrence of the impropersearch resulted from the incorrect transcription.
 3. The method of claim2, wherein the determining an occurrence of an improper search furthercomprises determining the occurrence of an improper search according toone or more of: whether no electronic content was selected by theelectronic content search system as a result of the search; whetherelectronic content selected by the electronic content search system as aresult of the search has an associated relevance score less than apredetermined value; whether the terms of the transcription are notconnected or weakly connected in a knowledge graph of terms of theelectronic content; or whether the terms of the transcription havepopularity scores below a predetermined value.
 4. The method of claim 2,wherein the determining that the occurrence of the improper searchresulted from the incorrect transcription further comprises determiningthe presence of the incorrect transcription according to one or more of:whether a transcription score of the transcription corresponding to theimproper search is less than a predetermined value; whether one or moreterms of the transcription corresponding to the improper search have ahomonym; whether one or more terms of the transcription corresponding tothe improper search have a corresponding pronunciation difficulty metricgreater than a predetermined value; a noise level of a query resultingin the transcription corresponding to the improper search; whether oneor more terms of the transcription corresponding to the improper searchis a mispronounced term; or whether the transcription corresponding tothe improper search comprises more than one term.
 5. The method of claim2, further comprising, if the electronic content search system did notgenerate an occurrence of the improper search, transmitting for displayrepresentations of the electronic content selected by the electroniccontent search system.
 6. The method of claim 2, further comprisingconditionally performing the successively submitting if the electroniccontent search system generated an occurrence of the improper search andif the occurrence of the improper search resulted from the incorrecttranscription.
 7. The method of claim 2, further comprising, if theelectronic content search system generated an occurrence of the impropersearch and if the occurrence of the improper search did not result fromthe incorrect transcription, generating an error message andtransmitting for display representations of the electronic contentselected by the electronic content search system.
 8. The method of claim1, further comprising, if none of the different subsets results in aresulting transcription different from the incorrect transcription,generating an error message and generating for display representationsof the electronic content selected by the electronic content searchsystem.
 9. The method of claim 1, wherein the successively submittingfurther comprises successively submitting the different subsets as hintwords to the one or more automated speech recognition systems, untilmultiple ones of the resulting transcriptions differ from the incorrecttranscription.
 10. The method of claim 9, further comprising selecting amost common transcription of the resulting transcriptions that differfrom the incorrect transcription, submitting the most commontranscription to an electronic content search system for selectingelectronic content corresponding to the most common transcription, andtransmitting for display representations of the electronic contentselected by the electronic content search system from the most commontranscription.
 11. A system for correcting errors in searches forelectronic content resulting from incorrect transcriptions by anautomated speech recognition system, the system comprising: a storagedevice; and control circuitry configured to: for an incorrecttranscription output by one or more automated speech recognitionsystems, successively submit terms associated with different subsets ofterms of the transcription as hint words to the one or more automatedspeech recognition systems, until a resulting transcription output bythe one or more automated speech recognition systems differs from theincorrect transcription; and submit the resulting transcription to anelectronic content search system for selecting electronic contentcorresponding to the resulting transcription.
 12. The system of claim11, wherein the control circuitry is further configured to: determine anoccurrence of an improper search conducted by the electronic contentsearch system; and determine whether the occurrence of the impropersearch resulted from the incorrect transcription.
 13. The system ofclaim 12, wherein the determining an occurrence of an improper searchfurther comprises determining the occurrence of an improper searchaccording to one or more of: whether no electronic content was selectedby the electronic content search system as a result of the search;whether electronic content selected by the electronic content searchsystem as a result of the search has an associated relevance score lessthan a predetermined value; whether the terms of the transcription arenot connected or weakly connected in a knowledge graph of terms of theelectronic content; or whether the terms of the transcription havepopularity scores below a predetermined value.
 14. The system of claim12, wherein the determining that the occurrence of the improper searchresulted from the incorrect transcription further comprises determiningthe presence of the incorrect transcription according to one or more of:whether a transcription score of the transcription corresponding to theimproper search is less than a predetermined value; whether one or moreterms of the transcription corresponding to the improper search have ahomonym; whether one or more terms of the transcription corresponding tothe improper search have a corresponding pronunciation difficulty metricgreater than a predetermined value; a noise level of a query resultingin the transcription corresponding to the improper search; whether oneor more terms of the transcription corresponding to the improper searchis a mispronounced term; or whether the transcription corresponding tothe improper search comprises more than one term.
 15. The system ofclaim 12, wherein the control circuitry is further configured to, if theelectronic content search system did not generate an occurrence of theimproper search, transmit for display representations of the electroniccontent selected by the electronic content search system.
 16. The systemof claim 12, wherein the control circuitry is further configured toconditionally perform the successively submitting if the electroniccontent search system generated an occurrence of the improper search andif the occurrence of the improper search resulted from the incorrecttranscription.
 17. The system of claim 12, wherein the control circuitryis further configured to, if the electronic content search systemgenerated an occurrence of the improper search and if the occurrence ofthe improper search did not result from the incorrect transcription,generate an error message and transmitting for display representationsof the electronic content selected by the electronic content searchsystem.
 18. The system of claim 11, wherein the control circuitry isfurther configured to, if none of the different subsets results in aresulting transcription different from the incorrect transcription,generate an error message and generating for display representations ofthe electronic content selected by the electronic content search system.19. The system of claim 11, wherein the successively submitting furthercomprises successively submitting the different subsets as hint words tothe one or more automated speech recognition systems, until multipleones of the resulting transcriptions differ from the incorrecttranscription.
 20. The system of claim 19, wherein the control circuitryis further configured to select a most common transcription of theresulting transcriptions that differ from the incorrect transcription,submit the most common transcription to an electronic content searchsystem for selecting electronic content corresponding to the most commontranscription, and transmit for display representations of theelectronic content selected by the electronic content search system fromthe most common transcription. 21-30. (canceled)